Search engines, such as Internet search engines, have been in use for some time. Such search engines permit the user to form a search query using combinations of keywords to search through a web page database containing text indices associated with one or more distinct web pages. The search engine looks for matches between the search query and text indices in the web page database, and then returns a number of hits which correspond to URL pointers and text excerpts from the web pages that represent the closest matches.
Wolfram|Alpha®, a computational knowledge engine developed by Wolfram Research, Inc., provides an online service that answers factual queries by retrieving an answer from curated data, or computing the answer. Wolfram|Alpha® differs from traditional search engines in that Wolfram|Alpha® computes and/or provides an answer rather than providing a list of documents or web pages that might contain the answer.
Intelligent personal assistants are now available for use with smart phones and tablet computers. For example, some intelligent personal assistants use a natural language user interface to answer questions, make recommendations, and perform actions by delegating requests to a set of Web services. For instance, intelligent personal assistants may utilize speech recognition techniques to determine a user input, and may utilize speech synthesis techniques to provide an output to the user. Many currently available intelligent personal assistants are powered by Wolfram|Alpha®. For example, many currently available intelligent personal assistants forward user questions to Wolfram|Alpha®, which then determines answers to those questions and returns the answers to the intelligent personal assistants.